//引入nodejs内置标准库
const http = require("http");

const hostname = "127.0.0.1";
const port = 3000;

//创建服务的同时注册回调函数
//回调函数:特定场景才执行的函数
const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader("Content-Type", "text/plain");
  res.end("Hello World\n");
});

server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});
